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The laboratory analytical results are attached as Appendix 5 of this report. Soil Profile and Geologic Information The Site is depicted on the Geologic maps of the Sacramento-San Joaquin Delta, California (Atwater, 1982). The Site is depicted within a Holocene and/or upper Pleistocene map unit described as "alluvium of creeks from Corral Hollow drainage to Bushy Creek" (Plate 9). The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of Willows clay, partially drained, and Stomar clay loam (Plate 10) (USDA, 2018). The table below presents some selected properties of these soils: Table 1. Selected Properties of On-Site Soils (USDA, 1992) Soil Name Depth Unified Soil Salinity Soil Perme- Septic tank and Map (in) Class Reaction ability absorption Symbol Classification mmhos/cm pH (in/hr) fields Stomar clay 0-17 Clay loam; CL <2 6.6-7.3 0.2-0.6 Severe: loam, 0-2% 17-47 Clay loam, clay; CL, CH <2 6.6-8.4 0.06-0.2 peres slowly slopes, 252 47-60 Clay loam, silty clay <2 7.4-8.4 0.2-0.6 loam; CL Willows clay, 0-20 Clay; CH 2-8 7.9-9.0 <0.06 Severe: partially 20-60 Clay, silty clay; CL, CH >4 8.5-9.0 <0.06 peres slowly drained, 0- 2% slopes, 274 Note: The table descriptions do not necessarily reflect site-specific soil properties. See description of the map unit for composition and behavior characteristics of the map unit. Soil Borings On April 10, 2019, Live Oak excavated a shallow soil boring in the proposed septic disposal area of the Site for the purpose of conducting a percolation test. The boring was four inches in diameter, 3.36 feet deep, and was excavated by hand auger (Table 2). The location of the boring is indicated on Plate 11. The soil in the boring was similar to that described by the Soil Survey. Silty clay with sand was encountered to a depth of 1.25 feet, followed by sandy clay to the full depth of the hole. The soil log is presented on Plate 12. Discussion of Soil Litho/ogy Based on the soil observed in the boring, there appears to be limited potential for percolation. Sandy soils generally have a much greater potential for percolation than LOGE 1843 Page 5